include/boost/corosio/native/detail/reactor/reactor_stream_socket.hpp

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reactor_stream_socket.hpp

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1		//
2		// Copyright (c) 2026 Steve Gerbino
3		//
4		// Distributed under the Boost Software License, Version 1.0. (See accompanying
5		// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
6		//
7		// Official repository: https://github.com/cppalliance/corosio
8		//
9
10		#ifndef BOOST_COROSIO_NATIVE_DETAIL_REACTOR_REACTOR_STREAM_SOCKET_HPP
11		#define BOOST_COROSIO_NATIVE_DETAIL_REACTOR_REACTOR_STREAM_SOCKET_HPP
12
13		#include <boost/corosio/tcp_socket.hpp>
14		#include <boost/corosio/shutdown_type.hpp>
15		#include <boost/corosio/wait_type.hpp>
16		#include <boost/corosio/native/detail/reactor/reactor_basic_socket.hpp>
17		#include <boost/corosio/native/detail/reactor/reactor_descriptor_state.hpp>
18		#include <boost/corosio/detail/dispatch_coro.hpp>
19		#include <boost/capy/buffers.hpp>
20
21		#include <coroutine>
22
23		#include <errno.h>
24		#include <sys/socket.h>
25		#include <sys/uio.h>
26
27		namespace boost::corosio::detail {
28
29		/** CRTP base for reactor-backed stream socket implementations.
30
31		Inherits shared data members and cancel/close/register logic
32		from reactor_basic_socket. Adds the stream-specific remote
33		endpoint, shutdown, and I/O dispatch (connect, read, write, wait).
34
35		@tparam Derived The concrete socket type (CRTP).
36		@tparam Service The backend's socket service type.
37		@tparam ConnOp The backend's connect op type.
38		@tparam ReadOp The backend's read op type.
39		@tparam WriteOp The backend's write op type.
40		@tparam WaitOp The backend's wait op type.
41		@tparam DescState The backend's descriptor_state type.
42		@tparam ImplBase The public vtable base
43		(tcp_socket::implementation or
44		local_stream_socket::implementation).
45		@tparam Endpoint The endpoint type (endpoint or local_endpoint).
46		*/
47		template<
48		class Derived,
49		class Service,
50		class ConnOp,
51		class ReadOp,
52		class WriteOp,
53		class WaitOp,
54		class DescState,
55		class ImplBase = tcp_socket::implementation,
56		class Endpoint = endpoint>
57		class reactor_stream_socket
58		: public reactor_basic_socket<
59		Derived,
60		ImplBase,
61		Service,
62		DescState,
63		Endpoint>
64		{
65		using base_type = reactor_basic_socket<
66		Derived,
67		ImplBase,
68		Service,
69		DescState,
70		Endpoint>;
71		using self_type = reactor_stream_socket<
72		Derived, Service, ConnOp, ReadOp, WriteOp, WaitOp,
73		DescState, ImplBase, Endpoint>;
74		friend base_type;
75		friend Derived;
76
77		protected:
78		// NOLINTNEXTLINE(bugprone-crtp-constructor-accessibility)
79	13592x	explicit reactor_stream_socket(Service& svc) noexcept : base_type(svc) {}
80
81		protected:
82		Endpoint remote_endpoint_;
83
84		public:
85		/// Pending connect operation slot.
86		ConnOp conn_;
87
88		/// Pending read operation slot.
89		ReadOp rd_;
90
91		/// Pending write operation slot.
92		WriteOp wr_;
93
94		/// Pending wait-for-read operation slot.
95		WaitOp wait_rd_;
96
97		/// Pending wait-for-write operation slot.
98		WaitOp wait_wr_;
99
100		/// Pending wait-for-error operation slot.
101		WaitOp wait_er_;
102
103	13592x	~reactor_stream_socket() override = default;
104
105		/// Return the cached remote endpoint.
106	60x	Endpoint remote_endpoint() const noexcept override
107		{
108	60x	return remote_endpoint_;
109		}
110
111		// --- Virtual method overrides (satisfy ImplBase pure virtuals) ---
112
113	4418x	std::coroutine_handle<> connect(
114		std::coroutine_handle<> h,
115		capy::executor_ref ex,
116		Endpoint ep,
117		std::stop_token token,
118		std::error_code* ec) override
119		{
120	4418x	return do_connect(h, ex, ep, token, ec);
121		}
122
123	197776x	std::coroutine_handle<> read_some(
124		std::coroutine_handle<> h,
125		capy::executor_ref ex,
126		buffer_param param,
127		std::stop_token token,
128		std::error_code* ec,
129		std::size_t* bytes_out) override
130		{
131	197776x	return do_read_some(h, ex, param, token, ec, bytes_out);
132		}
133
134	197131x	std::coroutine_handle<> write_some(
135		std::coroutine_handle<> h,
136		capy::executor_ref ex,
137		buffer_param param,
138		std::stop_token token,
139		std::error_code* ec,
140		std::size_t* bytes_out) override
141		{
142	197131x	return do_write_some(h, ex, param, token, ec, bytes_out);
143		}
144
145	51x	std::coroutine_handle<> wait(
146		std::coroutine_handle<> h,
147		capy::executor_ref ex,
148		wait_type w,
149		std::stop_token token,
150		std::error_code* ec) override
151		{
152	51x	return do_wait(h, ex, w, token, ec);
153		}
154
155		std::error_code
156	23x	shutdown(corosio::shutdown_type what) noexcept override
157		{
158	23x	return do_shutdown(static_cast<int>(what));
159		}
160
161	207x	void cancel() noexcept override
162		{
163	207x	this->do_cancel();
164	207x	}
165
166		// --- End virtual overrides ---
167
168		/// Close the socket (non-virtual, called by the service).
169		void close_socket() noexcept
170		{
171		this->do_close_socket();
172		}
173
174		/** Shut down part or all of the full-duplex connection.
175
176		@param what 0 = receive, 1 = send, 2 = both.
177		*/
178	23x	std::error_code do_shutdown(int what) noexcept
179		{
180		int how;
181	23x	switch (what)
182		{
183	4x	case 0: // shutdown_receive
184	4x	how = SHUT_RD;
185	4x	break;
186	15x	case 1: // shutdown_send
187	15x	how = SHUT_WR;
188	15x	break;
189	4x	case 2: // shutdown_both
190	4x	how = SHUT_RDWR;
191	4x	break;
192	✗	default:
193	✗	return make_err(EINVAL);
194		}
195	23x	if (::shutdown(this->fd_, how) != 0)
196	✗	return make_err(errno);
197	23x	return {};
198		}
199
200		/// Cache local and remote endpoints.
201	8879x	void set_endpoints(Endpoint local, Endpoint remote) noexcept
202		{
203	8879x	this->local_endpoint_ = std::move(local);
204	8879x	remote_endpoint_ = std::move(remote);
205	8879x	}
206
207		/** Shared connect dispatch.
208
209		Tries the connect syscall speculatively. On synchronous
210		completion, returns via inline budget or posts through queue.
211		On EINPROGRESS, registers with the reactor.
212		*/
213		std::coroutine_handle<> do_connect(
214		std::coroutine_handle<>,
215		capy::executor_ref,
216		Endpoint const&,
217		std::stop_token const&,
218		std::error_code*);
219
220		/** Shared scatter-read dispatch.
221
222		Tries readv() speculatively. On success or hard error,
223		returns via inline budget or posts through queue.
224		On EAGAIN, registers with the reactor.
225		*/
226		std::coroutine_handle<> do_read_some(
227		std::coroutine_handle<>,
228		capy::executor_ref,
229		buffer_param,
230		std::stop_token const&,
231		std::error_code*,
232		std::size_t*);
233
234		/** Shared gather-write dispatch.
235
236		Tries the write via WriteOp::write_policy speculatively.
237		On success or hard error, returns via inline budget or
238		posts through queue. On EAGAIN, registers with the reactor.
239		*/
240		std::coroutine_handle<> do_write_some(
241		std::coroutine_handle<>,
242		capy::executor_ref,
243		buffer_param,
244		std::stop_token const&,
245		std::error_code*,
246		std::size_t*);
247
248		/** Shared readiness-wait dispatch.
249
250		Every wait type probes the descriptor with a zero-timeout
251		`poll()` and completes at once if the condition already
252		holds; otherwise the op re-probes under the descriptor mutex
253		and parks, completing when a reactor event arrives and a
254		fresh probe confirms the condition. A write wait therefore
255		completes only while a non-blocking write can make progress.
256		*/
257		std::coroutine_handle<> do_wait(
258		std::coroutine_handle<>,
259		capy::executor_ref,
260		wait_type,
261		std::stop_token const&,
262		std::error_code*);
263
264		/** Close the socket and cancel pending operations.
265
266		Extends the base do_close_socket() to also reset
267		the remote endpoint.
268		*/
269	40764x	void do_close_socket() noexcept
270		{
271	40764x	base_type::do_close_socket();
272	40764x	remote_endpoint_ = Endpoint{};
273	40764x	}
274
275		/// Release ownership of the descriptor and drop the cached peer.
276	6x	native_handle_type do_release_socket() noexcept
277		{
278	6x	auto fd = base_type::do_release_socket();
279	6x	remote_endpoint_ = Endpoint{};
280	6x	return fd;
281		}
282
283		private:
284		// CRTP callbacks for reactor_basic_socket cancel/close
285
286		template<class Op>
287	223x	reactor_op_base** op_to_desc_slot(Op& op) noexcept
288		{
289	223x	if (&op == static_cast<void*>(&conn_))
290	5x	return &this->desc_state_.connect_op;
291	218x	if (&op == static_cast<void*>(&rd_))
292	203x	return &this->desc_state_.read_op;
293	15x	if (&op == static_cast<void*>(&wr_))
294	4x	return &this->desc_state_.write_op;
295	11x	if (&op == static_cast<void*>(&wait_rd_))
296	7x	return &this->desc_state_.wait_read_op;
297	4x	if (&op == static_cast<void*>(&wait_wr_))
298	2x	return &this->desc_state_.wait_write_op;
299	2x	if (&op == static_cast<void*>(&wait_er_))
300	2x	return &this->desc_state_.wait_error_op;
301	✗	return nullptr;
302		}
303
304		template<class Op>
305		bool* op_to_cancel_flag(Op& op) noexcept
306		{
307		if (&op == static_cast<void*>(&conn_))
308		return &this->desc_state_.connect_cancel_pending;
309		if (&op == static_cast<void*>(&rd_))
310		return &this->desc_state_.read_cancel_pending;
311		if (&op == static_cast<void*>(&wr_))
312		return &this->desc_state_.write_cancel_pending;
313		if (&op == static_cast<void*>(&wait_rd_))
314		return &this->desc_state_.wait_read_cancel_pending;
315		if (&op == static_cast<void*>(&wait_wr_))
316		return &this->desc_state_.wait_write_cancel_pending;
317		if (&op == static_cast<void*>(&wait_er_))
318		return &this->desc_state_.wait_error_cancel_pending;
319		return nullptr;
320		}
321
322		template<class Fn>
323	40977x	void for_each_op(Fn fn) noexcept
324		{
325	40977x	fn(conn_);
326	40977x	fn(rd_);
327	40977x	fn(wr_);
328	40977x	fn(wait_rd_);
329	40977x	fn(wait_wr_);
330	40977x	fn(wait_er_);
331	40977x	}
332
333		template<class Fn>
334	40977x	void for_each_desc_entry(Fn fn) noexcept
335		{
336	40977x	fn(conn_, this->desc_state_.connect_op);
337	40977x	fn(rd_, this->desc_state_.read_op);
338	40977x	fn(wr_, this->desc_state_.write_op);
339	40977x	fn(wait_rd_, this->desc_state_.wait_read_op);
340	40977x	fn(wait_wr_, this->desc_state_.wait_write_op);
341	40977x	fn(wait_er_, this->desc_state_.wait_error_op);
342	40977x	}
343		};
344
345		template<
346		class Derived,
347		class Service,
348		class ConnOp,
349		class ReadOp,
350		class WriteOp,
351		class WaitOp,
352		class DescState,
353		class ImplBase,
354		class Endpoint>
355		std::coroutine_handle<>
356	4418x	reactor_stream_socket<Derived, Service, ConnOp, ReadOp, WriteOp, WaitOp, DescState, ImplBase, Endpoint>::
357		do_connect(
358		std::coroutine_handle<> h,
359		capy::executor_ref ex,
360		Endpoint const& ep,
361		std::stop_token const& token,
362		std::error_code* ec)
363		{
364	4418x	auto& op = conn_;
365
366	4418x	sockaddr_storage storage{};
367	4418x	socklen_t addrlen = to_sockaddr(ep, socket_family(this->fd_), storage);
368		int result =
369	4418x	::connect(this->fd_, reinterpret_cast<sockaddr*>(&storage), addrlen);
370
371	4418x	if (result == 0)
372		{
373	27x	sockaddr_storage local_storage{};
374	27x	socklen_t local_len = sizeof(local_storage);
375	27x	if (::getsockname(
376		this->fd_, reinterpret_cast<sockaddr*>(&local_storage),
377	27x	&local_len) == 0)
378	✗	this->local_endpoint_ =
379	27x	from_sockaddr_as(local_storage, local_len, Endpoint{});
380	27x	remote_endpoint_ = ep;
381		}
382
383	4418x	if (result == 0 \|\| errno != EINPROGRESS)
384		{
385	31x	int err = (result < 0) ? errno : 0;
386	31x	if (this->svc_.scheduler().try_consume_inline_budget())
387		{
388	✗	*ec = err ? make_err(err) : std::error_code{};
389	✗	op.cont.h = h;
390	✗	return dispatch_coro(ex, op.cont);
391		}
392	31x	op.reset();
393	31x	op.h = h;
394	31x	op.ex = ex;
395	31x	op.ec_out = ec;
396	31x	op.fd = this->fd_;
397	31x	op.target_endpoint = ep;
398	31x	op.start(token, static_cast<Derived*>(this));
399	31x	op.impl_ptr = this->shared_from_this();
400	31x	op.complete(err, 0);
401	31x	this->svc_.post(&op);
402	31x	return std::noop_coroutine();
403		}
404
405		// EINPROGRESS — register with reactor
406	4387x	op.reset();
407	4387x	op.h = h;
408	4387x	op.ex = ex;
409	4387x	op.ec_out = ec;
410	4387x	op.fd = this->fd_;
411	4387x	op.target_endpoint = ep;
412	4387x	op.start(token, static_cast<Derived*>(this));
413	4387x	op.impl_ptr = this->shared_from_this();
414
415	4387x	this->register_op(
416	4387x	op, this->desc_state_.connect_op, this->desc_state_.write_ready,
417	4387x	this->desc_state_.connect_cancel_pending, true);
418	4387x	return std::noop_coroutine();
419		}
420
421		template<
422		class Derived,
423		class Service,
424		class ConnOp,
425		class ReadOp,
426		class WriteOp,
427		class WaitOp,
428		class DescState,
429		class ImplBase,
430		class Endpoint>
431		std::coroutine_handle<>
432	197776x	reactor_stream_socket<Derived, Service, ConnOp, ReadOp, WriteOp, WaitOp, DescState, ImplBase, Endpoint>::
433		do_read_some(
434		std::coroutine_handle<> h,
435		capy::executor_ref ex,
436		buffer_param param,
437		std::stop_token const& token,
438		std::error_code* ec,
439		std::size_t* bytes_out)
440		{
441	197776x	auto& op = rd_;
442	197776x	op.reset();
443
444	197776x	capy::mutable_buffer bufs[ReadOp::max_buffers];
445	197776x	op.iovec_count = static_cast<int>(param.copy_to(bufs, ReadOp::max_buffers));
446
447	197776x	if (op.iovec_count == 0 \|\| (op.iovec_count == 1 && bufs[0].size() == 0))
448		{
449	4x	op.empty_buffer_read = true;
450	4x	op.h = h;
451	4x	op.ex = ex;
452	4x	op.ec_out = ec;
453	4x	op.bytes_out = bytes_out;
454	4x	op.start(token, static_cast<Derived*>(this));
455	4x	op.impl_ptr = this->shared_from_this();
456	4x	op.complete(0, 0);
457	4x	this->svc_.post(&op);
458	4x	return std::noop_coroutine();
459		}
460
461	395556x	for (int i = 0; i < op.iovec_count; ++i)
462		{
463	197784x	op.iovecs[i].iov_base = bufs[i].data();
464	197784x	op.iovecs[i].iov_len = bufs[i].size();
465		}
466
467		// Speculative read; for the single-buffer case use recv() so the
468		// kernel skips the readv iov_iter setup.
469		ssize_t n;
470	197772x	if (op.iovec_count == 1)
471		{
472		do
473		{
474	197764x	n = ::recv(this->fd_, bufs[0].data(), bufs[0].size(), 0);
475		}
476	197764x	while (n < 0 && errno == EINTR);
477		}
478		else
479		{
480		do
481		{
482	8x	n = ::readv(this->fd_, op.iovecs, op.iovec_count);
483		}
484	8x	while (n < 0 && errno == EINTR);
485		}
486
487	197772x	if (n >= 0 \|\| (errno != EAGAIN && errno != EWOULDBLOCK))
488		{
489	197031x	int err = (n < 0) ? errno : 0;
490	197031x	auto bytes = (n > 0) ? static_cast<std::size_t>(n) : std::size_t(0);
491
492	197031x	if (this->svc_.scheduler().try_consume_inline_budget())
493		{
494	157662x	if (err)
495	✗	*ec = make_err(err);
496	157662x	else if (n == 0)
497	15x	*ec = capy::error::eof;
498		else
499	157647x	*ec = {};
500	157662x	*bytes_out = bytes;
501	157662x	op.cont.h = h;
502	157662x	return dispatch_coro(ex, op.cont);
503		}
504	39369x	op.h = h;
505	39369x	op.ex = ex;
506	39369x	op.ec_out = ec;
507	39369x	op.bytes_out = bytes_out;
508	39369x	op.start(token, static_cast<Derived*>(this));
509	39369x	op.impl_ptr = this->shared_from_this();
510	39369x	op.complete(err, bytes);
511	39369x	this->svc_.post(&op);
512	39369x	return std::noop_coroutine();
513		}
514
515		// EAGAIN — register with reactor
516	741x	op.h = h;
517	741x	op.ex = ex;
518	741x	op.ec_out = ec;
519	741x	op.bytes_out = bytes_out;
520	741x	op.fd = this->fd_;
521	741x	op.start(token, static_cast<Derived*>(this));
522	741x	op.impl_ptr = this->shared_from_this();
523
524	741x	this->register_op(
525	741x	op, this->desc_state_.read_op, this->desc_state_.read_ready,
526	741x	this->desc_state_.read_cancel_pending);
527	741x	return std::noop_coroutine();
528		}
529
530		template<
531		class Derived,
532		class Service,
533		class ConnOp,
534		class ReadOp,
535		class WriteOp,
536		class WaitOp,
537		class DescState,
538		class ImplBase,
539		class Endpoint>
540		std::coroutine_handle<>
541	197131x	reactor_stream_socket<Derived, Service, ConnOp, ReadOp, WriteOp, WaitOp, DescState, ImplBase, Endpoint>::
542		do_write_some(
543		std::coroutine_handle<> h,
544		capy::executor_ref ex,
545		buffer_param param,
546		std::stop_token const& token,
547		std::error_code* ec,
548		std::size_t* bytes_out)
549		{
550	197131x	auto& op = wr_;
551	197131x	op.reset();
552
553	197131x	capy::mutable_buffer bufs[WriteOp::max_buffers];
554	197131x	op.iovec_count =
555	197131x	static_cast<int>(param.copy_to(bufs, WriteOp::max_buffers));
556
557	197131x	if (op.iovec_count == 0 \|\| (op.iovec_count == 1 && bufs[0].size() == 0))
558		{
559	4x	op.h = h;
560	4x	op.ex = ex;
561	4x	op.ec_out = ec;
562	4x	op.bytes_out = bytes_out;
563	4x	op.start(token, static_cast<Derived*>(this));
564	4x	op.impl_ptr = this->shared_from_this();
565	4x	op.complete(0, 0);
566	4x	this->svc_.post(&op);
567	4x	return std::noop_coroutine();
568		}
569
570	394264x	for (int i = 0; i < op.iovec_count; ++i)
571		{
572	197137x	op.iovecs[i].iov_base = bufs[i].data();
573	197137x	op.iovecs[i].iov_len = bufs[i].size();
574		}
575
576		// Speculative write; the single-buffer case dispatches to a
577		// backend-specific fast path so the kernel skips msghdr/iov_iter
578		// setup (and so each backend can pick the right SIGPIPE strategy).
579		ssize_t n;
580	197127x	if (op.iovec_count == 1)
581		{
582	394242x	n = WriteOp::write_policy::write_one(
583	197121x	this->fd_, bufs[0].data(), bufs[0].size());
584		}
585		else
586		{
587	6x	n = WriteOp::write_policy::write(
588	6x	this->fd_, op.iovecs, op.iovec_count);
589		}
590
591	197127x	if (n >= 0 \|\| (errno != EAGAIN && errno != EWOULDBLOCK))
592		{
593	196998x	int err = (n < 0) ? errno : 0;
594	196998x	auto bytes = (n > 0) ? static_cast<std::size_t>(n) : std::size_t(0);
595
596	196998x	if (this->svc_.scheduler().try_consume_inline_budget())
597		{
598	157565x	*ec = err ? make_err(err) : std::error_code{};
599	157565x	*bytes_out = bytes;
600	157565x	op.cont.h = h;
601	157565x	return dispatch_coro(ex, op.cont);
602		}
603	39433x	op.h = h;
604	39433x	op.ex = ex;
605	39433x	op.ec_out = ec;
606	39433x	op.bytes_out = bytes_out;
607	39433x	op.start(token, static_cast<Derived*>(this));
608	39433x	op.impl_ptr = this->shared_from_this();
609	39433x	op.complete(err, bytes);
610	39433x	this->svc_.post(&op);
611	39433x	return std::noop_coroutine();
612		}
613
614		// EAGAIN — register with reactor
615	129x	op.h = h;
616	129x	op.ex = ex;
617	129x	op.ec_out = ec;
618	129x	op.bytes_out = bytes_out;
619	129x	op.fd = this->fd_;
620	129x	op.start(token, static_cast<Derived*>(this));
621	129x	op.impl_ptr = this->shared_from_this();
622
623	129x	this->register_op(
624	129x	op, this->desc_state_.write_op, this->desc_state_.write_ready,
625	129x	this->desc_state_.write_cancel_pending, true);
626	129x	return std::noop_coroutine();
627		}
628
629		template<
630		class Derived,
631		class Service,
632		class ConnOp,
633		class ReadOp,
634		class WriteOp,
635		class WaitOp,
636		class DescState,
637		class ImplBase,
638		class Endpoint>
639		std::coroutine_handle<>
640	51x	reactor_stream_socket<Derived, Service, ConnOp, ReadOp, WriteOp, WaitOp, DescState, ImplBase, Endpoint>::
641		do_wait(
642		std::coroutine_handle<> h,
643		capy::executor_ref ex,
644		wait_type w,
645		std::stop_token const& token,
646		std::error_code* ec)
647		{
648		// Pick refs up-front to avoid duplicating the register_op call.
649		WaitOp* op_ptr;
650		reactor_op_base** desc_slot_ptr;
651		bool* cancel_flag_ptr;
652		std::uint32_t event;
653
654	51x	if (w == wait_type::read)
655		{
656	21x	op_ptr = &wait_rd_;
657	21x	desc_slot_ptr = &this->desc_state_.wait_read_op;
658	21x	cancel_flag_ptr = &this->desc_state_.wait_read_cancel_pending;
659	21x	event = reactor_event_read;
660		}
661	30x	else if (w == wait_type::write)
662		{
663	16x	op_ptr = &wait_wr_;
664	16x	desc_slot_ptr = &this->desc_state_.wait_write_op;
665	16x	cancel_flag_ptr = &this->desc_state_.wait_write_cancel_pending;
666	16x	event = reactor_event_write;
667		}
668		else // wait_type::error
669		{
670	14x	op_ptr = &wait_er_;
671	14x	desc_slot_ptr = &this->desc_state_.wait_error_op;
672	14x	cancel_flag_ptr = &this->desc_state_.wait_error_cancel_pending;
673	14x	event = reactor_event_error;
674		}
675
676	51x	auto& op = *op_ptr;
677
678		// Speculative probe, mirroring the speculative read: an
679		// edge-triggered reactor cannot report a condition that already
680		// holds, so a wait initiated on an already-ready socket would
681		// otherwise park forever.
682	51x	int perr = 0;
683	51x	if (WaitOp::probe(this->fd_, event, perr))
684		{
685	18x	if (this->svc_.scheduler().try_consume_inline_budget())
686		{
687	4x	*ec = perr ? make_err(perr) : std::error_code{};
688	4x	op.cont.h = h;
689	4x	return dispatch_coro(ex, op.cont);
690		}
691	14x	op.reset();
692	14x	op.wait_event = event;
693	14x	op.h = h;
694	14x	op.ex = ex;
695	14x	op.ec_out = ec;
696	14x	op.fd = this->fd_;
697	14x	op.start(token, static_cast<Derived*>(this));
698	14x	op.impl_ptr = this->shared_from_this();
699	14x	op.complete(perr, 0);
700	14x	this->svc_.post(&op);
701	14x	return std::noop_coroutine();
702		}
703
704	33x	op.reset();
705	33x	op.wait_event = event;
706	33x	op.h = h;
707	33x	op.ex = ex;
708	33x	op.ec_out = ec;
709	33x	op.fd = this->fd_;
710	33x	op.start(token, static_cast<Derived*>(this));
711	33x	op.impl_ptr = this->shared_from_this();
712
713		// Force register_op's ready path so the wait op re-probes under
714		// the descriptor mutex before parking. An edge consumed between
715		// the speculative probe above and the park (a concurrent short
716		// read, or an error event dispatched to an empty slot) would
717		// otherwise leave the wait parked on a ready socket.
718	33x	bool force_probe = true;
719	33x	this->register_op(op, desc_slot_ptr, force_probe, cancel_flag_ptr,
720		event == reactor_event_write);
721	33x	return std::noop_coroutine();
722		}
723
724		} // namespace boost::corosio::detail
725
726		#endif // BOOST_COROSIO_NATIVE_DETAIL_REACTOR_REACTOR_STREAM_SOCKET_HPP
727